Pt. 383m (SN 643 476) – Sub-Trichant addition
There has been an addition to the list of Y Trichant – The 300m Hills of Wales, with the summit height, bwlch height
and their locations, the drop and status of the hill derived from detail on
contemporary maps produced from Ordnance Survey data and LIDAR analysis
conducted by Myrddyn Phillips.
The criteria for the list that this addition
applies to are:
Y Trichant
– The 300m Hills of Wales – Welsh
hills at or above 300m and below 400m in height that have 30m minimum drop, with an accompanying sub list entitled the
Sub-Trichant, with the criteria for this sub category being all Welsh hills at
or above 300m and below 400m in height with 20m or more and below 30m of
drop. The list is authored by Myrddyn Phillips with the
Introduction to the list and the renaming of it appearing on Mapping Mountains
on the 13th May 2017, and the Introduction to the Mapping Mountains
publication of the list appearing on the 1st January 2022.
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Y Trichant - The 300m Hills of Wales by Myrddyn Phillips |
The hill is being listed by the point (Pt. 383m)
notation as an appropriate name for it either through local enquiry and/or
historic research has not been found by the author, and it is adjoined to the
Esgair Wen group of hills, which are
situated in the central part of South Wales (Region B, Sub-Region B1), and it is positioned enclosed by minor roads, with
the B4343 road farther to its north-west and the A482 road farther to its south-west,
and has the town of Llanbedr Pont Steffan (Lampeter) towards the west.
After the sub list was standardised, and
interpolated heights and drop values also included the details for this hill
were re-evaluated and it was listed with 18m of drop, based on the 383m summit
spot height that appears on the Ordnance Survey 1:25,000 Explorer map and the
365m bwlch spot height that appeared on the Ordnance Survey Vector Map Local
hosted on the Geograph website and which was entitled the Interactive Coverage
Map.
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Extract from the Ordnance Survey 1:25,000 Explorer map |
However, it was not until LIDAR became available
that the details for this hill could be accurately re-assessed. The LIDAR (Light Detection & Ranging)
technique produced highly accurate height data that is now freely available for
much of England and Wales.
Therefore, the addition of this hill to
Sub-Trichant status is due to detail on contemporary maps produced from
Ordnance Survey data and LIDAR analysis, resulting in a 383m summit height and
a 361.9m bwlch height, with these values giving this hill 21m of drop, which is
sufficient for it to be classified as a Sub-Trichant.
The full details for the
hill are:
Group: Esgair Wen
Name: Pt. 383m
OS 1:50,000 map: 146
Summit Height: 383m (spot height)
Summit Grid
Reference: SN 64358 47680 (spot height)
Bwlch Height: 361.9m (LIDAR)
Bwlch Grid
Reference: SN 64555 47855 (LIDAR)
Drop: 21m (spot height summit and LIDAR bwlch)
Myrddyn Phillips (May 2023)
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